Apparatus for molding hollow concrete walls



Dec. 15 1925.

A. G. \N. WEDBERG APPARATUS FOR MOLDI NG HOLLOW CONCRETE WALLS OriginalFiled May 5. 20' 2 Sheets-Sheet l m m n A Dec. 15,1925. 1,566,263

A. G.'\N- WEDBERG APPARATUS FOR MOLDING HOLLOW CONCRETE WALLS OriginalFiled May 5, 1920 2 Sheets-Sheet 2 i; F, M I Z mm k v M .7. m

A TTORNEYS Patented Dec. 15, 1925.

UNITED STATES PATENT OFFICE.

AXEL e. w. WEDBERQZOF'FLORAL i ARK, Lone ISLAND, NEW YORK.

APPARATUS FOR MOLDING HOLLOW CONCRETE WALLS.

Application filed May 8, 1920, Serial No. 878,533.

' tus for molding hollow concrete walls, the

object being primarily to economically produce a monolithic structurecharacterized bydead air spaces or chambers for heat and cold insulationpurposes and wherein certain strata of concrete at the inner surface andthe outer surface of the wall are ]01I1ed in such a way as to addstability to the wall. and at the same time minimize the filtration ofmoisture through the material composing the wall.

In carrying into practice the process of this invention, there isutilized a plurality of vcllapsible'forms assembled in a certain orderwithin a space bounded by an exterior form, said collapsible forms beingpositioned to leave spaces between the margins of the collpasible formsand within the exterior form, which spaces are charged with concretematerial in such manner as to result in the production of an innerconcrete strata and an outer concrete strata, the two strata beingjoined, and the whole producing a section. of a wall of definitethickness, height and length. After molding such a wall section, theinterior forms are collapsed so as to free or release the same from themolded wall section, and'they are raised to definite positions and againassembled sothat a further section of the wall is molded upon the wallsection first molded, and these operations are repeated until theseveral walls are completed.

I According to the mode of procedure, I employ spacers for separatingthe collapsible forms, said spacers being positioned intermediate theedge portions of the forms and said spacers being separated relativelyto each other and mechanically connected for handling as a unit, saidspacers operating to mold webs which join the inner and outer strata ofthe wall. These spacers are intended to be displaced after the operationof molding the wall shall have been completed, and this results inconcrete webs of narrow cross section, the same being advantageousRenewed November. 22, 1921. Serial No. 517,152.

torthe reason that the quantity of concrete in the webs is minimized soas to reduce the filtration of moisture through the wall in rainy ordamp weather.

Another part of the invention consists in the collapsible form the bodyof which is a continuous sheet, or substantially continuous, sheet ofmetal of a desired cross section, and'with the marginal portions inoverlapping relation. Within the space bounded by the metal body isencased an operating mechanism embodying a plurality of rock shafts,certain levers, and links, so connected and arranged as to rigidly lockthe metallic body when in operative position, and which mechanism can beoperated easily so as to slide one marginal portion of the body upon theother marginal portion, thereby reduc- Figure 2 is a sectional plan viewthereofin the plane of the dotted line 22 of Figure 1.

Figure 3 is a sectional plan View on the line 33 of Figure 1 of a partof the collapsible form at the overlapping part of its metal body,showing on an enlarged scale the locking means for said lapping partthereof.

Figure 4 is a sectional side elevation illustrating at differentsections the formation of a hollow concrete wall as the product of themethod in accordance with this invention.

Figure 5 is a cross section showing the collapsible form within anexterior form for molding the concrete wall.

Figure 6 is a vertical cross section on the line 6-6 of Figure 4 showingthe completed wall.

Figures 7 and 8 are horizontal sectional views of the completed wall inthe planes of the dottedlines 7-7 and 88 respectively of Figure 4. 4

Figure 9 is a horizontal detail section illustrating the relation of aspacer to two adjacent collapsible forms.

Figure 10 is a detail perspective view of a series of the connectedspacers.

In carrying my invention into practice, it is preferred to employcollapsible forms, a preferred construction being shown in Figures 1, 2and 3. Said form embodies a continuous shell or casing A, composedpreferably of a continuous, or substantially con tinnous, metal sheet,the same being of a length suitable for the purpose and of a desiredcrot's section, such as the oval cross section illustrated in Figure 2.The shell is stiffened by the employment of a number of metallic straps,a, positioned internally and at suitable intervals, said straps beingsuitably aflinied to the metal body. The shell is open at the top andbottom and in the top edge thereof is provided a plurality of notches b.The marginal edges of the shell are positioned in lapping contact asshown in Figure 2 and more clearly inclicated in Figure 3, the saidlapping edges being formed in a particular way to pro vide for therequired collapsing of the form in order to free it from surface contactwith the moldedconcrete. As shown in Figure 3, the ec ge (Z is folded ordoubled baekwardly upon itself so as to produce an overhanging lip dwith an intermediate space (F, whereas the other margin or edge e of themetal shell is formed with a rib c, the latter being pro vided with aweb 6 and with a lip 6 The ribbed part c of the margin 6 extendsinwardly so as to position the web 6 in the space (Z between theoverhanging lip cl and the marginal edge (Z, thus affording the desiredoverlap of one part 6 to the other part (Z of the shell, theconstruction and arrange ment being such as to allow the one part tohave a limited sliding movement relatively to the other part providedsaid overlapping parts are free from restraint. The marginal part i.extended well beyond the web (2 so as to result in a'nose f which istapering and has a desired close contact with the marginal part (Z, andin this marginal part (i adjacent the line of overlap is a plurality ofslots g, the latter accommodating the cam heads B of a plurality oflocking levers B. These levers are positioned interiorly of thecollapsible form, at suitable intervals in the length thereof, eachlever being pivoted on a fulcrum bolt Z) supported in brackets 7/ fixedto the inside of the sheet metal body A. The cam head B of each leverterminates in a hook b which, in the operative position of the levershown in Figures 2 and 3, is forced through the slot 9, so that the hookis in contact with the lip c of marginal part 6, and as a result ofpivoting the lev r to the marginal part (Z. said lever B and its camhead B operates to lock the two parts d, e, from sliding movementrelatively to each other.

The levers B form parts of a system of locking devices positionedinteriorly of the metal shell for internally stiffening said shell soasto resist the compression of the concrete material in the process ofmolding the hollow wall. Associated with the system of locking devicesjust referred to are a plurality of rock shafts C, D, independent ofeach other and mounted for rotative movement in appropriate brackets, c,fixed at desired intervals to the interior of the shell A. Said rockshafts extend lengthwise of the shell, for nearly the length thereof,and at the upper end of each shaft it is provided with means, such asthe polygonal stud cl, and with a crank C for the purpose of applyingpower to said shafts, and each of them, so as to rotate the shaft C orDin the bearings. As shown in Figure 1, the crank C it fitted to thestuds (Z of the two shafts, and remains applied to said shafts below thetop edge of the shell, so as to preclude rota-tive movement of saidshafts.

The rock shaft D is provided at intervals corresponding to the spacingapart of levers B, with crank arms E, to the outer ends of which arepivoted links E, the other ends of which links are pivoted to the outerends of said levers B.

The levers B and links E are adapted to have thrust bearing contact witha ledge afforded by an angle iron E attached to the inside of the shellA, and as the lever B is pivoted at b to one side of the shell, whereasthe thrust bearing afforded by the angle iron E is on the opposite sideof the shell, the levers B, cranks E, and links E afford means forstiffening the shell internally thereof.

The other rock shaft C is provided at intervals with double cranks F,each having two arms f. To one arm 7 of each double crank F is pivotedone end of a lever G, the other end of which is pivoted at q to one sideof the shell, said pivoted end of the lever having in the operativeposition shown in Figure 2 a-thrust bearing against an angle ironfixedly attached to the inside of the shell. To the other arm f of eachdouble crank F is pivoted one end of a link H, the other end of whichlink is mounted on the bolt of one lever B. As will be noted byreference to Figure 2, the rock shaft C is mounted on the shell at oneside thereof, whereas the levers G are pivoted at g to the opposite sideof the shell, and, fun ther, said rock shaft C is connected by thelevers and the links H with the opposite sine wall of the shell so thatthe levers B, E, the links E and H and the two rock shafts constitute aplurality of devices distributed or spaced within the shell for am- 1stiffening the latter internally thereof shaft 1) so as to break thetoggle afforded by arms E, links E and levers B, the effect of which isto withdraw the cam heads B from the lip 6 and thereafter the operatorapplies the crank to the shaft C and rotates the latter, thus releasingthe levers G and links H from the locking effect of the toggle G H. Therotation of the shafts C D successively and the operation of the partsas sociated therewith imparts sliding movement of the marginal part c tothe other corresponding part (i of the shell A, whereby said shell is soreduced in its cross sectional dimension as to release said shell fromsurface contactfrom themolded material.

A desired number of the collapsible forms heretofore described areutilized in the process of molding a hollow wall according to thisinvention and substantially as depicted in Figures 4 and 8 inclusive ofthe drawings.

According to this part of the invention, a foundation I is firstprovided in any way known to the art, it being usual to moldthefoundation I from concrete material in v a well known manner. During theinstallation of the concrete foundation, it is preferred to attach tothe top edge thereof a plurality of narrow centering members, i, thesame being shown in Figures 4, 5 and 6 as thin metal strips, the saidstrips being par tially embedded in the concrete material of thefoundation so as to allow the top edge of the centering strips toproject for an appreciable distance above the top edge of saidfoundation I, said strips i being positioned substantially centrallywith referenceto the top face of said foundation, see Figure 4.

A desirednumber of collapsible forms, each of the character heretoforedescribed,

are positioned within an external mold, J

story of the building to be erected, and,fur-

ther, said external mold is equal in length to the foundation, althoughthe dimensions "are I the'spacer blocks in each vertical series henotmaterial.

Positioned within the external mold J are a desired number of thecollapsible forms A, the same resting upon the foundation.

V The collapsible forms are spaced relatively to each other, and arespaced,'also, with-respect to the side walls of theexternal mold, theeffect of which spacing of the forms relatively to the external moldv isto produce the external strata and the internal strata of concreterequisite for theproduc tion of the wall, whereas the spacing of theforms relatively to eachother results iirthe molding of the concrete toproduce bridge: members, the latter operating to join the outer andinner strata of the concrete'wall, see Figures 6, 7 and 8.

The spacing of the collapsible forms in the desired order within theexternal mold is effected by spacer blocks K interposed between 'the'narrow portions of the oval forms, see Figure 9. A row of these spacerblocks is employed between two adjacent forms, see the left hand portionof Figure 4, and for convenience in handling the row of spacer blocks toenable the row to be positioned as a unit within the external mold, theblocks of said row are mechanically connected by'a metal strip K, seeFigure 10.

The blocks are wedge shaped in cross section, each block being providedin its longitudinal faces with concave seats 0, the curvature of whichconforms to the radius of the metal shells A of the collapsible forms atthe narrow end portions thereof, see Figure 9. The mechanical bond K inthe form bf a strip is fitted in a recess 0 provided in one concave faceof each block K, in order that said strip K may be arranged flush withthe blocks of the row, and said blocks K and the bonding strip arefastened together by suitable means, such as by the screws 79, wherebythe blocks of each row are adapted to be handled as a unit.

The row of blocks K operate primarily to space the" collapsible forms,and in addi' tion-to this function said blocks serve the purposeofretaining the forms in operative positions within the external mold, forthe reason that the cross sectionally curved end portions of said formsare in contact with the concave seats 0 of said blocks K, see

Figure 9, thus positioning the forms A accurately within the externalmold prior to pouring and tamping the concrete.

The row of blocks are required to be positioned and retained accuratelywithin the external mold J, and to this end thelowermost block of eachrow is provided with a notch or recess 7', see Figures 4; and 10, whichnotch or recess receives the centering memher 2' attached to thefoundation I.

The vertical series of Wedge shaped spacer blocks :K occupies the spacebetween the narrow portions of two adjacent forms A.

ing separated with reference to each other, see F gures 4' and 10. Thespacer blocks K are displaceable from the concrete material aftermolding and setting of such material,

theeflect of which is to leaveslots k in the webs 7a which join theinner strata m-to the outer strata m of the material comprising thehollow wall M, see Figures 6 to 8 inclusive.

After placing the desired number of collapsible forms A in positionwithin the external mold, and prior to dumping in the mixed concretematerial, it is preferred to fixedly lock said collapsible forms inposition by the employment of a top locking member, shown in Figures 4and 5 as a T shaped bar L which is received in the notches I) providedin the top edges of the collapsible forms. This locking member is flushwith the top edges of the collapsible forms, or substantially so, andover each form A is positioned a cover 0, the latter closing the chamberof said collapsible form so as to preclude the entry of concretematerial into the form.

The operation of molding a hollow wall of concrete material is asfollows :After the centering strips 2' are molded in the foundation, theexternal mold J is erected thereon, and the desired number ofcollapsible forms A and the required rows of spacer blocks K, are placedwithin said external mold, said spacer blocks K being positioned betweenthe forms A and in contact therewith so as to accurately locate thecollapsible forms within the external mold and to retain said forms inoperative positions within said mold J. The row of spacer blocks arelocated by the strips 71 on the foundation, and are retained inv placeby said strips 5. The forms are locked together at their upper ends bythe T bar L, and covers 0 are placed upon the upper ends of said formsA. Concrete material is now deposited in the mold so as to fill thespaces intervening the external mold and the forms A, and also to fillthe spaces between the forms A except where the concrete is excluded bythe spacing blocks K, the concrete being tamped as is usual. Theconcrete material is allowed to stand for a proper time in order that itmay set and harden, after which the T bar L is removed and the forms Aare collapsed, whereupon. the external mold is removed, and thereuponsaid external mold and the forms A may be reset for molding the secondstory of the building according to the procedure herein disclosed; butprior to resetting the forms for molding the upper story or stories,keys L are set in the slots of the concrete, said keys serving thepurpose of a support for the forms A when placed in position upon thepart of the wall previously molded; the keys L being so positioned uponthe concrete as to support the forms, A in a manner to preclude theconcrete poured for molding the upper story from passing'below the keysand into the spaces M of the hollow wall.

The, operation of molding a wall as herein described produces a hollowwall characterized by air spaces or chambers M and composed of an outerstrata m and an inner strata m of concrete material, which strata arejoined by webs hen the wall is set and the forms A are withdrawn, thewedge shaped blocks K should be driven out of the concrete material inthe web 70, such displacement of the blocks resulting in the formationofslots 7c in the connecting webs it" between the inner and outer strataof material. The presence of these slots is desirable for the reasonthat they reduce the volume of concrete material in the connecting websis, thus minimizing the seepage of moisture through the concretematerial in wet weather. It is not desired to restrict the invention tothe use of displaceab le spacer blocks between the collapsible forms forthe reason that I may, in some cases, omit said spacer blocks and resortto the employment of metallic bridge pieces as the connecting meansbetween the outer strata and the inner strata of the concrete material.

Having thus fully described the invention, what I claim as new anddesire to secure by Letters Patent is:

1. A collapsible form for molding hollow concrete walls embodying a bodyformed of a substantially continuous shell, and means on the edgeportions of said body for limiting the movement of said edge portions soas to preclude a relative separating movement between said edge portionsand the formation of an opening or space intermediate said edgeportions, in combination with operating means for expanding andcontracting said body.

2. A collapsible form for molding hollow concrete walls embodying abody, the margins of which are flanged and overlapped to preclude arelative separating movement and to secure a limited sliding movement bywhich the form is expanded and collapsed, in combination with operatingmeans positioned internally of the body and including elements by whichthelapped edges are restrained from sliding movement.

3. A collapsible form for molding hollow concrete walls embodying a bodythe margins of which are flanged and overlapped to preclude a relativeseparating movement and to secure a limited sliding movement by whichthe form is expanded and collapsed, in combination with a plurality oflevers for locking said lapping edge portions against relative movement,and a system of toggle devices for internally stiffening the body andfor actuatingsaid levers to lock and release the lapped edge portions ofthe body.

4:. A collapsible form for molding hollow concrete walls embodying abody the margins of which are flanged and overlapped to preclude arelative separating movement and to secure a limited sliding movement bywhich the form is expanded and collapsed, in combination with aplurality of rock shafts, a plurality of locking elements operated byone of said shafts for locking and releasing the lapping edge portionsof the body, and a plurality of toggle devices operated by the otherrock shaft for expanding and contracting the body.

5. In an apparatus for molding hollow concrete walls, the combinationwith an external mold, and collapsible forms within said mold, of spacerelements free from mechanical attachment to said collapsible forms, saidspacer elements being positioned for surface contact with adjacentcollapsible forms.

6. In an apparatus for molding hollow concrete walls, the combinationwith an external mold, and. a plurality of collapsible forms positionedwithin said mold, of a row of spacer elements in contact with saidcollapsible forms, the elements of said row being separated one from theother to allow the formation of bridge members in molding the wall fromconcrete.

7. In an apparatus for molding hollow concrete walls, the combinationwith an external mold, and a plurality of collapsible forms positionedwithin said mold, of a row of spacer elements positioned within the moldand in contact with adjacent forms, and means for mechanicallyconnecting the spacer elements of said row.

8. In an apparatus for molding hollow concrete walls, the combinationwith an ex ternal mold, and a plurality of collapsible. forms positionedwithin said mold, of a connected row of spacer elements, and meanscontacting with a spacer element of said row for initially locating therow of spacer elements with reference to the positions to be occupied bythe collapsible forms.

9. In an apparatus for molding hollow concrete walls, the combinationwith an external mold, and a plurality of collapsible forms positionedwithin said mold, of a row of spacer elements positioned intermediatesaid forms, each spacer element being provided with a seat conforming tothe cross sectional contour of the form and in contact therewith.

10. In an apparatus for molding hollow concrete walls, the combinationwith an external mold, and a plurality of collapsible forms positionedwithin said-mold, of a row of spacer elements positioned within the moldand intern'iediate said forms, said spacer elements being in contactwith said forms and operating to retain the latter within the moldduring the period of charging said mold with concrete, and means forlocating said row of spacer elements within said external mold.

11. In an apparatus for molding hollow concrete walls, the combinationwith an external mold, and collapsible forms positioned therein, of aspacer-locating strip arranged within the external mold at the bottomthereof, and a connected row of spacer blocks the lower one of which isnotched for engagement with said spacer-locating strip, said spacerblocks contacting said collapsible forms.

12. In an apparatus for molding hollow concrete walls, the combinationwith an external mold, and a plurality of collapsible forms positionedwithin said mold, of a row of spacer elements separated one from theother, and a strip attached to said spacer elements and connecting thesame to the end that the row of spacer elements are adapted to behandled as a unit.

13. In an apparatus for molding hollow concrete walls, the combinationwith an external mold, and a plunlity of collapsible forms positionedwithin said mold, of a row of connected spacer blocks, the lower one ofwhich is provided with a notch, and a fixed positioning member extendinginto said notch for locating the row of spacer blocks within the mold.

14. In an apparatus for molding hollow concrete walls, the combinationwith an external mold, and a plurality of collapsible forms positionedtherein, of a row of spacer elements in contact with said forms and forlocating the latter with reference to the external mold, and bars forlocking the forms in position relatively to the external mold.

15. In an apparatus of the class described, the combination with anexternal mold, and a plurality of forms positioned therein to produce amold space, of a spacer carrying member, means for locating said spacercar rying member in definite relation to said forms, and a plurality ofspacer elements supported by said spacer carrying member.

16. In an apparatus of the class described, the combination with anexternal mold, and a plurality of forms positioned therein to produce a'mold space, of web molding elements positioned intermediate said forms,said web molding elements being connected together in a relativelyseparated position by a strip to leave openings intermediate said webmolding elements, said openings being in communication with the moldspace.

17. In an apparatus of the class described, the combination with anexternal mold, and a plurality of forms positioned therein to produce amold space, of web molding ele ments positioned intermediate said forms,said web molding elements being wedge shaped in cross section and beingconnected together in a relatively spaced position by a strip to leaveopenings intermediate said elements.

In testimony whereof, I have signed my name hereto this 28 day of April,1920.

AXEL G. W. VVEDBER.

